X-ray angle indicator



HOWARD RILEY RAPER, 0F .ALBUQUERQUE, NEW MEXICO.

X-RAY ANGLE INDICATOR.

`Specification of Letters Patent.

Patented Mar. 7, 1922.

Application led January 3, 1921. Serial No. 434,775.

To all whoml it may concern:

Be it known that I, Howann RILEY RAPER, a citizen of the United States,residing at Albuquerque, in the county of Bernalillo and State of NewMexico, have invented certain new and useful Improvements in X-Iay AngleIndicators, of which the following is a s oeciication. i

his invention relates toan X-ray angle indicator for use on X-raymachines to automatically show the angle at which the X-ray tube isinclined to the horizontal,

'and is particularly adapted to inform thel operator of the correctrange of angles for inclining the` X-ray tube in dental. radiography,although useful in radiography of any part of the cranium and the bodywhereever it is necessary to incline the tube to a predetermined angleto obtain the desired result.

As my invention has particular usefulness in dental radiography it ishereinafter described as adapted for that purpose: but it is to beunderstood thatthe specific disclosure and explanation in thatconnection is not to be deemed as restricting the application of theinvention to that branch of radiography alone. It is to be understood.however. that one branch of the invention is specific to dentalradiography, to-wi t, the chart or dial which I have invented based onmuch research work and many experiments, which has angles and indicia bywhich the operator of the X-ray machine may accurately predetermine theangle to the horizontal at which the cone and tube of the machine shouldbe set to obtain a radiograph of any particular tooth, whether molar,cuspid. bicuspid or incisor` and on' either the upper or lower jaw.which will accurately disclose the conditions prevailing at thatparticular tooth and thus enable diagnoses. within reasonablelimitations of accuracy. to be obtained.

This chart or dial is set` forth and claimed in my application SerialNo. 3477i filed Jan. 3,1921.

.In respect to the other branch of my 1nvention. that having to do withthe use of the angle indicator in connection with, or carried'byQanX-ray tube` a pointer, and a plumb, and disregarding the special dentalindicia. the invention has a'wider range of usefulness than in dentalradiography as it enables the X-ray tube to be properly intrue picturewould clined to make radiographs of the Cranium and any desired part oftheb'ody.

The art of radiography involves the principles of castmg shadows, towit,a source ofl light, and object. and a screen' `or surface on whlchthe'shadow falls. In dental X-ray work, the X-ray tube corresponds tothe source of light, the tooth and the contiguous parts to the object,and the surface of the filrri to the screen on which they shadow is casDepending on the relationship existing between the light, the object and.the surface. a shadow may assume the trueiorm of the object. or. it mayassume a fantastic, distorted form thereof. It therefore becomesnecessary in order to obtain a true shadow, to establish a correctrelationship between the light. the object and the surface.

In dental radiography the teeth and contiguous parts and the film arenot subject to extreme variation of position. The diiiiculty ofobtaining radiographs which truly disclose the condition of a giventooth and contiguous parts is to properly locate and incline the X-raytube. -If the head of the patient is placed so that the roots of theteeth are substantially v e'rtical and the film is placed in the mouthsothat. it presses against the tissues close to the teeth. twofofthematerial lfactors have been taken care of. The third factor is theadjustment of the X--ray tube-in correct position to obtain the correctradiographic image.

Heretofore the operator of the X-ray rnachine has depended solely uponjudgment or natural aptitude or intuition for the properangular'arrangementrof the tube to meet any given condition and object as towhether a true or distorted radiograph is desired. For. it will beunderstood that distortion. i. c.. elongation of the picture toiamoderate degree. sometimes affords a better view of certain diseaseconditions than a shortening would completely obscure. Some operatorsobtain a picture of the'ends of the roots at the expense of goodreproduction of vthe balance of the teeth. while others obtain goodpictures of unable to catch the end of the'rootl on the film. )theroperators appear unable to approximate the proper angle for any 'give-ntooth.

From the foregoing, and a wide variety of 110 disclose and which oretheteeth and yet appear angleto tlie'liorizontal at which the X-ray tubeset, whether .itbe--inclined upwardly or downwardly; and second, itfurnishes instant information to the dental radiographer ot the rangesor limits oit angles which must not be exceeded in making a radiograpliof any/given tooth, Whether molar, cuspid, bi-

cuspid or incisor on either the upper or lower jaw, it' an accuraterepresentation of conditions is to be obtained. The invention thereforeleaves little to the jut ginent or intuition or sense7 ot' position onthe part ot' 'theoperaton and saves time, ser I"ice, and expense in thisclass of Work.

The epresent invention may be embodied .in hand-carried or "portableform, or, attached to the tube of'anX-ray machine or otherwisearranged.y ln Whatever embodiment it assumes, there is a plumb-pointerwhich' automatically indicates the angle at which'the X-ray tube isinclined. There is also a set'table pointer Ior hand which may be movedto the predetermined angle-marking or indication on the dial or chart toaittord a guide for quickly determining thel proper position for theplumb-pointer.

The disclosure of the invention hereinafter given is, therefore, to beconsidered as illustrative of the invention and notin limitation of thescope thereof or the utilization of the-essentiel principles involved.

. ln theaecoinpanying drawings i-Fig 1 is a detail riew ot' ahand-carried or, portable form ot ,the invention shown in position asbeing applied to the cone or cylinder of the tube of an X-ray apparatus,illustrating. ythe downward inclination thereof at an angle of 300 aswould be the case urhen-an upper molar was being4 radioigraplied. i

y Fig. .2 a similar riew showing the cone inclined upwardly at an angleof 100, as .'vould-be the case when a lower bicuspidwas beingradiograpl'ied.A

" Fig.- 3iis a View oi a modification Where.

the dial-or chart is attached .to the X-ray tube or cylinder, the latterbeinginclined downwardly lat ai.' angle off 300.' l Fig. 4 is anenlarged View of the dialused Aon both forms of the invention showninthe preceding figures, the plumb being swung to one side to show thatitis independentof thepointer; and l y, Figfois a diagram of anupperbicuspid "and tufol iilms, 'illustrating the necessity for myinclination of the X-ray tube at the properif'. t.' i "-;"w" w f f A.

rgleff In Fig. tube-1 having cone la'. My invention may be 1 I havepart4 of sinful-ray.l i

1 ,essere ,vicewhich is held in the operators hand.

lt may, however, be attached toitliefcone or cylinder in any desired orpreferred manner, as shown, for instance, in Figs. 3 and e.

A dial 2 in the form of a. semi-disk, carries vindicia which is theresultI ot' numerous eX- periments and much research work on myV part;Then the invention is embodied in portable forni, as disclosed in Figs'land 2, the dial 2 may be provided with a handle 2iX which is grasped 'bythe operator. The dial may, however, be carried by a supporting` stand,or by a bracket on the X-ray apparatus. rlhis dial, when attached to thecone l, as shown in: Figs. 3 and Ll, is in effect,

a part ot the X- ray tube and is adapted to be moved up and down, orlaterally, with the tube. ln any embodiment of the linvention the dialmay be opaque or transparent. Piyoted to the'dial at the same point,which is indicated by 3, are a plumb Il and asettable pointer 5.Eitheror both ot these may be of some distinctive color, it desired. Theplumb l always maintains a Vertical position and by its relationshiptolfith'if linesv and indicia'o'n the dial 2, indicates to the ioperator' the angle to which the tubel is tilted, y*either 'upwardly ordou'nuardly. The settable pointer 5 is rictionally held at the pivot 3to a degree sufficient to maintain it in any position to which it may beswung.

lt is a simple matter to set the pointer 5 to the proper position on thedial 2' and then swingthe tube 1 until the pointer'coincides With the`plumb 4.

The dial 2 has a Zero line 6 which is at right'anglesto the longitudinalaxis of the tube 1 and cone la. i Consequently when the plumb 4tcoincides with theline 6, the tube l and cone 1a are preciselyhorizontal. The dial i2 comprises twoquadrants 2, i, on opposite sidesof the zero line 6. The quadrant 2a is laid outfand mar red asa 'guidefor radiog;raphinnr upper teeth. The quadrant 2by is laid out and markedas a Iguidefor radiographing lower teeth.

By-research Aand experiment l have dis- ,.coyered that there are certainranges or limits otang'ular disposition of the X-ray tube within whichthe operator must 'keep .when radiopji'aphing molars, bicuspids," in-.cisoi's and cuspids on the upper jaw and that entirely different rangesol anglesumust be observed when taking IX-ray pictures of molurs,ljiic'uspids` incisors and cuspids on theloiverJaw.,v rl`hese angles areas follows:

llpper incisore/from 350 to `450 above the horizontal.

`lines 7. 7a, indicating Cuspids, from 400 to 50 above the horizontal.

Bicuspids, from 25o to 10 above the horizontal.

Molars. from :25 to 350 above the horizontal.

L0 wel' teeth.

Incisors and cuspids, from 10` to 20C below the horizontal. Lowerbicuspids, horizontal.

Lower molars, from 0"4 (i. e. the horizontal) to 10o below thehorizont-al.

Failure to obtain accuratel and complete radiographs will result itthese limits are not observed. Undoubtedly the failureA o operators toobtain roper radiographs of any given tooth has een the result of lackof knowledge of lthe proper angle (within a given range) at which theX-ray tube should be inclined. So t'ar as I am aware, 1 am the first toinvent means. in the form of a chart. dial. or other disclosure. whichpresents this grapher. whether in the form of a dial or chart alone. ora dial or chart used in connection with an indicating device whichautomatically. so to spe-ak, discloses the tact that the tube is at theproper angle for the taking of a radiograph of a particular tooth.

Radiatinv from the point 3 ot' the dial on the quadrants Qa and 2*.respectively. are the different angles. each line being provided withthe angle from 50 to 15O below the designation. as 10. 20. 30. etc.

I The word molar is provided Von the dial between the anglesrepresenting the limits of inclination of the tube 1 for X-raying amolar. For instance. on the quadrant Q the word. molar runs from theangle line 25 to the angle line Jfor upper teeth. Similarly. as theproper range of angular disposition for bicuspids is between 25o and 10for upper teeth. the word bicuspids is provided and comprehended betweenthe angle lines Q5 and 40 on the quadrant 2a. The word incisors appearsbetween the angle line@ 5 and 15 for upper teeth. The word cuspidsappears between the angle lines 10 and 50 for upper teeth on quadrant2a.

To further assist the operator colors may be employed in the form otlmarkings corresponding to the ranges between angles. For instance. a redband S represents the range of angles for taking radiographs for molars;a green band 9. the range for bicuspide: a jvellow band 10. the rangefor incisors: and a blue band 1'1. the range for cuspids.v

As a further aid to the operator. pictures of the different teeth may beprovided a shown at 12. 13. 14, 15. a',

The same plan of indication and identitication heretofore described forthe quadrant information' to the radio-' Certain conditions are metwithin X-ray Y dental work where there is a malformation or tipping-ot theteeth. The dial 2 may be provided with Vindicia representing properangles at meet such conditions. if desired. although this is not shown.

1 have ascertained by lresearch that the following angles for the tube 1should be observed: l I

Lower molars tipped away to the lingual: 10O above the horizontal.

F or eXtra-oral lateral dental radiographs: 65C to T50 above thehorizontal.

pper'teeth with the iilm placed horizontally in the mouth: about 60above the hori- Zontal.

l'pper molars when the vault is very high: as low as 20.-

If these angles are observed. about ot cases will be properlyradiographed: but in extreme malpos1tion of teeth. extreme angles arerequired.

The anglesA hereinbefore given are based on ythe assumption that thepatients head will be so placed that the teeth will be disposedsubstantially vertically,

)Iy invention has to do. more particularly. with the inclination of theX-ray tube for vertical angles. The invention does not lend itself tothe determination of horizontal angles. but Vas successful dentalradiography depends largely7 on the .correct determination ot verticalangles. the invention provides means for insuring successful radiographsin averv high percentage of cases.

Assuming. b v way of illustration. that an upper molar is to beradiographed and that 300 (midwa)v between the limits 25 and 350) is theangle to which the tube 1 is to be set. this indication appearing onquadrant- 2a where the word molar and the red band S appear. theoperator immediately moves the pointer 5 to the 30 point. Knowing theparticular tooth which is to be radiographed, the operators evenaturally seeks the word. color and tooth representation on the dial 2.

TVhen the portable form shown in Figs. 1 and 2 is used. the device ispositioned underneath or alongside the cone 1a in such manner that thestraight edge QXx is against the cone or tube or assumes a position inalignment with the longitudinal axis thereof. The tube being tilteduntil the plumb 4 -aligns with the pointer 5. it is known that the tubeis at the proper degree of inclinawhich the tube lshould be set tolWafrdly and brought tothe proper tion for radiographingthe particulartboth in question. ln Figs. l and 2 the device is sho wn 1as beingapplied to the tube or cone.

When the angle meter is attached to the cone l?, by' any suitable meansas in 23 and 4:, and the pointer havingr been set to the 300 mark, ifthe tube is tilted downwardly until the pointer 5 aligns with ltheVplumb t, it is known that the tube is at the proper degree ofinclination.v

In both forms ot the i1i"venti m the indi cationis automaticallyregistered. I

liecording to Whether thel tooth to be radiographed is on the upper orlower jaw, the tube l must bey tilted downwardly or. `upn predeternmined angle, as the case may be.

VF, is a film 'placed in a more or less vertical position in the mouth.HF. is a tilni placed horizontally in the mouth.y The abcess cavity Willregister between lines A and B when the X-rays are directed through theparts as indicated by arrow No. l.4 But the abscess cavity Wiil not showwhen the X-rays are directed through the parts as indicated 'by arrowNo. 2. The placing of the film in the mouth horizontally (HF)necessitates the use of the high-above angle of the rays ing 'angieindications (arrow lilo.v 2), Therefore, the placing of the hlm 1n themouth in this position iscon-` traindicated when one wishes to maire avcareful examination for periapical infection.

What I. claim lis:

L An angle indicating chart or dial for use in connection With X-raymachines, hav-I r and teeth identifying indicia showing the correctrangeV of angles for inclination ot' the 'X-ray tube for any tooth, andmeans for automatically indicat-y ing on. said chart or dial thedifferent anygles and indicia thereof.

2.*An angle indicating chart or dial for use in connection with X-raymachines, having angle indications and teeth identifying indicia showingthe correct range of angles for inclination ot the iXi-ray tube for anytooth, and a plumb for automatically indieating on said chartor dial thedifferent angles and indicia thereof.

3.,An/ angle indicating chart or dial for use in connection with X-raymachines, having angle indications land teeth identifying indiciashowing the correct range ot angles for inclination ot' the fil-ray tube'tor any tooth, a plumb 'for automatically indicating" on said chart ordial the different angles and meente indicia thereof. and a settablepointer nihich may be positioned to point to an)Lr angle or indicia. onsaid chart or dial. f

4. The coinbin tion with the lli-rai' tube of an X-ray machine, of anangle indicating chart or dial carriedvby said tube and having:r angle`indications and teetivfidentitying in` dicia showing the correct rangeot angles for inclination of the X-ray tube tor anyv tooth, and meansfor automaticalhv indicating on said chart or dial the different anglesand indicia tbereofas lthe tube is tilted.

The combination with the X-ray'tube angle indications and teethidentitying'in! dicia showing` the correct range of angles torinclination of the X-ray tube for any tooth, and a plumb `forautomatically indicatingA on said chart or dial the different angles an(inchart or dial carried by said tube andhaving angle indications andteeth identifying in# diciashoiving ,the correct range oi'an/gles forinclination of the X-ray tube vtorany tooth,`a plumb for automaticallyindicating on said chart or dial theditterent angles 'and indiciathereotl as the tube is tiltt-ithandav settable pointer which may be.'positioned to point toany angle'or indicia 'on said chart or dial.

7. The combination `with the X-ray tube yotl an X- ray machine. of anangle indicating# chart or dial ca rrled by said tube and having ot anX-ray machine` of an angle indicati-ingr chart of semi-diskshape carriedbysaid tube" and coniprlsing two quadrants, one quadrant bearinziG4angle inclinations for downward inclination of the X-ray tube and thelother quadrant bearing' angle ,inclina-i tions for upward inclination ofthe 15x-ray',

tube, a plumb adapted to automatically show the angle of inclinationwhen the tube' is tilted, and a pointer which may be set toV point toauf/,angle or indicia on either quadrant. l

,8.- The combination with the X-ray' tube oi an Xray machine, oi3 anangle indicating chart or dial carried by said X-ray tube. Va plumbadapted ftoiautomatically show the I angle ot' inclination of the tube,either upwardly or downwardly Jfrom theh'orizont'al. and a settabiepointer for indicating-any angle on said chartor dial.4

in testimony whereof l affix my signatinfe.)l

now-inn einer Barna.

